fix(ui): default UI scale is 100% — native size out of the box (#1074)

New installs rendered at 130% zoom, which read as oversized on typical
displays. Fresh sessions now start at 100%; anyone who already picked a
scale keeps it (uiScale is persisted and wins over the default).

Co-authored-by: mergetest <test@local>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

frontend/src/store/uiSlice.ts

@@ -101,7 +101,9 @@ export const createUiSlice: StateCreator<UiSlice, [], [], UiSlice> = (set, get)
   isSidebarProjectsCollapsed: false,
   sidebarTab: 'projects',
   showCheatsheet: false,
-  uiScale: 1.3,
+  // 100% by default — the app renders at native size out of the box; users
+  // who prefer larger UI pick their scale in Settings → Appearance (persisted).
+  uiScale: 1.0,
 
   setMode: (mode) => set({ mode }),
   setDefineMethod: (method) => set({ defineMethod: method }),